In modern medicine, laser has been used in the various form. Medical application of laser, which was limited to the surgical area, has been widely extended to non-vascular diagnostic and therapeutic areas in recent years. First, laser was unreduced into surgical procedure and laser introduced into surgical area has high output energy and functions tissue destruction. High level laser was applied, through the tissue destruction phenomenon, to tissue cutting, coagulation and hemostasis. Then, low level laser therapy began to be applied to the treatment of wound at first. Researches for clinical effect and photobiological, photochemical reaction of low level laser have been carried on, reported on healing of damaged tissues, analgesic effect, anti-inflammatory effect, anti-edema effect, tissue vascular change and stimulation effect on the cell, and low level laser is used in many areas of medicine, as examples, in treatment of wound, tissue defects, etc. in dermatology, inner ear diseases, ear infections, etc. in otolaryngology, bruises, contusion, etc. in acupuncture, aphthous stomatilis, gingivitis, etc. in dentistry, rheumatoid arthritis, sprains, etc. in orthopedics.
In the case such as arthritis or dermatitis, while current treatment method in the form of medicated patch put on the affected area such as or medicine for oral administration have side effects such as festering of affected area or gastrointestinal dysfunction when used for long period and are less effective due to passive delivery of efficacy, method to project the laser light, which is not in direct contact with human body, doesn't have a side effect of festering of affected area and the treatment effect can be maximized by using algorithm which can generate the laser light creating proper treatment effect when projected to the affected area.
Meanwhile, photochemical action for plant can be observed in carbon dioxide assimilation and for the living body, it has been known that when illuminating light. APT is produced by the optical action and cells are activated. In other words, laser light, if illuminated on the living body with low energy not to burn in-vivo cells, has effects in activating the physiological function of living body and promoting natural healing power of affected area, which has been well known in the medical field through experiences in surgical procedure already having used high level laser.
Recently, low level laser therapy (LLLT) has been developed to treat various diseases actively using this action and begins to be used in several disease areas.
Biochemical action of light is depends on wavelength, polarization, and intensity of light and, according to experimental results, it has been known that polarized light with energy of around 100 mW in the range of 600 um ˜1000 um has the greatest effect on human body.
Such light can be generated using He˜Ne laser, semiconductor laser or YAG laser with semiconductor laser being favorable in terms of size or price, and now semiconductor laser with GaAs (904 nm), GaAlAs (780-820-870 nm), InGaAlP (630-685 nm) as material is mainly developed and sold.
However, emitted light of LED has been reported to be available instead of laser, and is adopted in the product which regards especially production cost as important. Although beam width of LED can not be narrowed below the certain level and it is not polarized because LED is not a coherent light as a laser. LED generates the light of the range of 600˜1000 nm and can produce similar effect when semiconductor laser is used as long as the intensity of around 100 mW/cm is guaranteed.
Currently, the most prevalent in the low level laser therapy (LLLT) are the various pain treatments, which was greatly developed because of the large effects on elimination of pain discovered after Prof. Plog, Canada examined the He—Ne laser on the meridian point as the form of laser acupuncture.
Researches for clinical effect and photobiological photochemical react ion of low level laser have been carried on, reported on healing of damaged tissues, analgesic effect, anti-inflammatory effect, anti-edema effect, tissue vascular change and stimulation effect on the cell, and low level laser is used in many areas of medicine.
However, conventional form of laser therapy device is treated as medical equipment and large in volume so that is can be used restrictedly in certain medical institutions such as hospitals or health centers, and has a drawback of large production cost.
In addition, the range of illumination of laser light doesn't reach deep into the inside, and therefore there is an difficulty in effective treatment.
Furthermore, the existing devices comprise the structure wherein the earpiece fastened to the ears is blocked from the outside, and has an disadvantage of inflammation in the inner ear caused by the heat generated by laser, due to no ventilation with the air.